fix(sql): don't classify objects with permissive __getattr__ as connections

[Jayashanker-Padishala]

This pull request was authored by a coding agent. (Per AGENTS.md: authored by Claude Code under the direction of @Jayashanker-Padishala, who takes responsibility for it. Marked as draft per policy.)

Fixes #10213

📝 Summary

Instantiating any ignite.metrics.Metric hung the executing cell forever. Root cause (found via faulthandler stack dump of the hung kernel):

1. ignite metrics implement __getattr__ to return a lazy MetricsLambda factory for any attribute name — and each access runs traceback.format_stack() (ignite metric.py:797), so every attribute probe is also slow.
2. That makes every callable(getattr(var, method, None)) duck-typing check succeed, so the post-execution _broadcast_data_source_connection hook classified the metric as an ADBC connection.
3. AdbcConnectionCatalog.get_databases → adbc_get_objects(...).read_all().to_pylist() then walked into the lazy object graph and never produced real data — the cell appears hung and is not interruptible.

🔧 Fix

Add fabricates_attributes() (in _sql/engines/types.py): probe one attribute that no real connection defines; if the object returns something for it, its duck-typing answers are meaningless and is_compatible rejects it. Applied to both AdbcDBAPIEngine and DBAPIEngine (the two engines relying on pure getattr duck-typing — the others use isinstance checks).

Deliberately not inspect.getattr_static: genuine connection-pool proxies legitimately forward __getattr__ to an underlying connection and would regress; they pass the probe (the probe attribute doesn't exist on the real connection either).

This generalizes the existing ibis Deferred special-case (#7791) — any permissive-__getattr__ object (lazy proxies, mocks) is now handled, not just known names.

🧪 Verification

• Reproduced the hang in the interactive kernel (executing_kernel fixture + from ignite.metrics import Loss; metric = Loss(nn.MSELoss())): watchdog fired at 30s pre-fix; post-fix the same cell completes in ~4s with metric defined.
• New tests: test_is_compatible_rejects_fabricated_attributes (dbapi), test_adbc_is_compatible_rejects_fabricated_attributes (adbc), test_fabricated_attributes_not_treated_as_engine (get_engines).
• pytest tests/_sql/: 246 passed. ruff check + ruff format --check clean on all changed files.

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[Jayashanker-Padishala]

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[Light2Dark]

Thanks @Jayashanker-Padishala! I made a similar fix here with some additions #10301. But thank you for checking, appreciate it.